Cultured excised root development

In the meantime, the formation of the main alkaloids in C. ipecacuanha under a variety of conditions has been extensively investigated emetine (1) in callus cultures (49) and under the effects of L-tyrosine supplementation (5t)) emetine (1) and cephaeline (2) in Panamanian ipecac (57), in Nicaraguan ipecac (52), in regenerates obtained by clonal propagation (53,54), in tissue cultures (55) and under the effects of exogenous feeding of shikimic acid and L-phenylalanine (55), in cell suspension and excised root cultures (57), in adventitious root cultures (58), and in callus cultures (56,59) and the effects of age and electrokinetic potential (60) ipecoside (7) in the roots (61) and the effect oi Azotobacter, leaf mold, and farmyard manure on alkaloid content (62). In addition, micropropagation systems for C. ipecacuanha have been developed (63-65). 

Considerable interest has been shown recently in genetically transformed root cultures for the production of secondary metabolites. In order to develop hairy root cultures in the laboratory, surface-sterilized plant tissue is inoculated with a suspension of A. rhizogenes and, after a period of incubation (generally between 1-6 weeks) at 24-28°C, transformed roots emerge at the infection sites. After elimination of the excess bacteria, the excised roots are incubated in liquid culture medium. The genetically transformed roots grow faster than do untransformed roots, they are highly branched and they can be cultivated in hormone-free... 

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